1. Field
The following description relates to a method and an apparatus to measure bioimpedance.
2. Description of Related Art
Skin, blood, muscles, tissues, joints, and other portions or organs of a body produce an impedance with a value including a resistance component and a capacitor component in response to current flowing through the body. The impedance value refers to a bioimpedance. Based on the bioimpedance, body fat or body fluid components may be estimated. The bioimpedance is obtained by applying a low-frequency current signal to a body of a user and measuring a voltage signal between measurement electrodes.
A bioelectrode used to measure the bioimpedance includes a wet electrode and a dry electrode. The wet electrode uses an electrolyte solution for surface treatment to reduce an interface impedance of a surface on which the electrode and skin of the user are contacted. Conversely, the dry electrode does not use an electrolyte to measure a biosignal, for example, the bioimpedance. As a result, the dry electrode has a greater interface impedance than the wet electrode.